1H-Imidazole
- Formula: C3H4N2
- Molecular weight: 68.0773
- IUPAC Standard InChI: InChI=1S/C3H4N2/c1-2-5-3-4-1/h1-3H,(H,4,5)
- IUPAC Standard InChIKey: RAXXELZNTBOGNW-UHFFFAOYSA-N
- CAS Registry Number: 288-32-4
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Imidazole; Glyoxalin; Glyoxaline; Imidazol; Imutex; Methanimidamide, N,N'-1,2-ethenediyl-; Miazole; 1,3-Diaza-2,4-cyclopentadiene; 1,3-Diazole; Formamidine, N,N'-vinylene-; Iminazole; IMD; Pyrro(b)monazole; USAF EK-4733; NSC 60522
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Condensed phase thermochemistry data
Go To: Top, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°solid | Ccb | Zaheeruddin and Lodhi, 1991 | uncertain value: 59.96 kJ/mol; ALS | ||
| ΔfH°solid | 49.8 ± 0.6 | kJ/mol | Ccb | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986; ALS |
| ΔfH°solid | 58.5 ± 3.3 | kJ/mol | Ccb | Bedford, Edmondson, et al., 1962 | Reanalyzed by Cox and Pilcher, 1970, Original value = 61. ± 3. kJ/mol; ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | Ccb | Zaheeruddin and Lodhi, 1991 | uncertain value: -1812.17 kJ/mol; ALS | ||
| ΔcH°solid | -1801.9 ± 0.5 | kJ/mol | Ccb | Jimenez, Roux, et al., 1987 | see Jimenez, Roux, et al., 1986; ALS |
| ΔcH°solid | -1810.6 ± 3.3 | kJ/mol | Ccb | Bedford, Edmondson, et al., 1962 | Reanalyzed by Cox and Pilcher, 1970, Original value = -1813.1 ± 3.3 kJ/mol; ALS |
| ΔcH°solid | -1802. | kJ/mol | Ccb | Zimmerman and Geisenfelder, 1961 | ALS |
Constant pressure heat capacity of solid
| Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 82.4 | 298.15 | Jimenez, Roux, et al., 1987 | Cp given as 1.21 J/g*K.; DH |
| 89.78 | 300. | DeWit, DeKruif, et al., 1983 | T = 90 to 370 K.; DH |
| 94.4 | 310. | DeWit, Offringa, et al., 1983 | T = 300 to 450 K.; DH |
References
Go To: Top, Condensed phase thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Zaheeruddin and Lodhi, 1991
Zaheeruddin, M.; Lodhi, Z.H.,
Enthalpies of formation of some cyclic compounds,
Phys. Chem. (Peshawar Pak.), 1991, 10, 111-118. [all data]
Jimenez, Roux, et al., 1987
Jimenez, P.; Roux, M.V.; Turrion, C.,
Thermochemical properties of N-heterocyclic compounds. I. Enthalpies of combustion, vapour pressures and enthalpies of sublimation, and enthalpies of formation of pyrazole, imidazole, indazole, and benzimidazole,
J. Chem. Thermodyn., 1987, 19, 985-992. [all data]
Jimenez, Roux, et al., 1986
Jimenez, P.; Roux, M.V.; Turrion, C.; Gomis, F.,
Thermochemical properties of some N-heterocyclic compounds,
J. Calorim. Anal. Therm. Thermodyn. Chim., 1986, 17, 469-470. [all data]
Bedford, Edmondson, et al., 1962
Bedford, A.F.; Edmondson, P.B.; Mortimer, C.T.,
Heats of formation and bond energies. Part VI. n-Butyliso-butyraldimine, n-butylisobutylamine, pyrazole, and imidazole,
J. Chem. Soc., 1962, 2927-2931. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Zimmerman and Geisenfelder, 1961
Zimmerman, H.; Geisenfelder, H.,
Uber die Mesomerieenergie von Azolen,
Z. Electrochem., 1961, 65, 368-371. [all data]
DeWit, DeKruif, et al., 1983
DeWit, H.G.M.; DeKruif, C.G.; Van Miltenburg, J.C.,
Thermodynamic properties of molecular organic crystals containing organic crystals containing nitrogen, oxygen, and sulfur. II. Molar heat capacities of eight compounds by adiabatic calorimetry,
J. Chem. Thermodynam., 1983, 15, 891-902. [all data]
DeWit, Offringa, et al., 1983
DeWit, H.G.M.; Offringa, J.C.A.; De Kruif, C.G.; Van Miltenburg, J.C.,
Thermodynamic properties of molecular organic crystals containing nitrogen, oxygen and sulfur. III. Molar heat capacities measured by differential scanning calorimetry,
Thermochim. Acta, 1983, 65, 43-51. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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